具杀虫活性雷公藤内生菌的分离与筛选

以卫矛科植物雷公藤的根、茎、叶为材料分离得到内生菌183株,其中真菌111株,放线菌23株,细菌49株。雷公藤植株的不同组织部位的内生菌数量有较大的差异,雷公藤根中分离得到的内生菌最多(89株),占总数的48.63%,叶部次之(72株),占总数的39.35%,茎部分离得到的内生菌最少(22株),占总数的12.02%。以卤虫、蚊幼及蚜虫为试虫,对183株内生菌的杀虫活性进行筛选,得到3株对蚜虫具有较高毒杀活性的菌株。其中菌株11-6-76的胞内和胞外代谢物均具有较高的杀蚜活性,蚜虫的死亡率分别为78.64%和70.75%;菌株11-3-37和12-2-47的胞内代谢产物提取物对蚜虫的毒杀活性较高,蚜虫死亡率分别为82.74%和76.97%。菌株11-3-37、11-6-76和12-2-47胞内代谢产物粗提物对蚜虫的LC_(50)分别为34.8mg/mL、31.2mg/mL和46.4mg/mL。

Isolation and Screening of Insecticidal Endophytes from Tripterygium wilfordii

183 isolates were separated from Tripterygium wilfordii Hook.f.,including 111 fungi,23 actinomycetes and 49 bacteria.There were 89 isolates separated from root,72 isolates from leaf,and 22 isolates from stem.The 183 isolates were tested on mosquito larvae and aphides,of which 3 isolates had high insecticidal activity.Intracellular and extracellular metabolites of isolate 11-6-76 had insecticidal activity against aphides with death rate of 78.64% and 70.75%,respectively.Intracellular metabolites of isolate 11-3-37 and 12-2-47 had insecticidal activity against aphides with death rate of 82.74% and 76.97%,respectively.Intracellular metabolites of isolate 11-3-37,11-6-76 and 12-2-47 had insecticidal activity against aphides with LC₅₀ of 34.8 mg/mL,31.2 mg/mL and 46.4 mg/mL,respectively.